Receiving system and method of processing data

ABSTRACT

A receiving system and a method of processing data are disclosed herein. The receiving system includes a receiving unit, a system information processor, a decoding unit, and a display unit. The receiving unit receives a broadcast signal including a 3D content and system information associated with the 3D content. The system information processor extracts identification information from the system information. Herein, the identification information may identify that the broadcast signal being received by the receiving unit includes the 3D content. The decoding unit decodes the received 3D content based upon transmission format information of the 3D content. Herein, the transmission format information may be included in the extracted identification information. And, the display unit displays the 3D content decoded by the decoding unit as a 3D image based upon a display method of a display device.

TECHNICAL FIELD

The present invention relates to a method and apparatus for processingan image signal and, more particularly, to a receiving system forreceiving and processing a 3-dimensional (3D) image signal and a methodof processing data.

BACKGROUND ART

Generally, a 3-dimensional (3D) image (or stereoscopic image) is basedupon the principle of stereoscopic vision of both human eyes. A parallaxbetween both eyes, in other words, a binocular parallax caused by thetwo eyes of an individual being spaced apart at a distance ofapproximately 65 millimeters (mm) is viewed as the main factor thatenables the individual to view objects 3-dimensionally. When each of theleft eye and the right eye respectively views a 2-dimensional (or flat)image, the brain combines the pair of differently viewed images, therebyrealizing the depth and actual form of the original 3D image.

Such 3D image display may be broadly divided into a stereoscopic method,a volumetric method, and a holographic method. For example, a 3D imagedisplay device adopting the stereoscopic method corresponds to an imagedisplay device that adds depth information to 2D images and that usessuch depth information to enable the viewer to experience the dynamic,live, and realistic perception of the 3D image.

Furthermore, the method of displaying 3D images may be broadly dividedinto a method of wearing special glasses and a method of not wearing anyspecial glasses.

DISCLOSURE OF INVENTION Technical Problem

Accordingly, the present invention is directed to a receiving system anda method of processing data that substantially obviate one or moreproblems due to limitations and disadvantages of the related art.

An object of the present invention is to provide a receiving system anda method of processing data that can recognize the reception of a 3Dimage by the receiving system.

Another object of the present invention is to provide a receiving systemand a method of processing data that can enable a receiving system beingunable to process 3D images to disregard the reception of any 3D image.

Additional advantages, objects, and features of the invention will beset forth in part in the description which follows and in part willbecome apparent to those having ordinary skill in the art uponexamination of the following or may be learned from practice of theinvention. The objectives and other advantages of the invention may berealized and attained by the structure particularly pointed out in thewritten description and claims hereof as well as the appended drawings.

Technical Solution

To achieve these objects and other advantages and in accordance with thepurpose of the invention, as embodied and broadly described herein, areceiving system includes a receiving unit, a system informationprocessor, a decoding unit, and a display unit. The receiving unitreceives a broadcast signal including a 3D content and systeminformation associated with the 3D content. The system informationprocessor extracts identification information from the systeminformation. Herein, the identification information may identify thatthe broadcast signal being received by the receiving unit includes the3D content. The decoding unit decodes the received 3D content based upontransmission format information of the 3D content. Herein, thetransmission format information may be included in the extractedidentification information. And, the display unit displays the 3Dcontent decoded by the decoding unit as a 3D image based upon a displaymethod of a display device.

Herein, the identification information may be included in a program maptable (PMT) of the system information in a descriptor format.

And, the identification information may be included in a virtual channeltable (VCT) of the system information in a descriptor format.

Herein, the identification information may further include a fieldindicating whether an uppermost pixel of a furthermost left side of areceived frame belongs to a left image or to a right image, a fieldindicating whether at least one of the left image and the right imagehas been inversely scanned and encoded, a field indicating which of theleft image and the right image has been inversely scanned, and a fieldindicating whether at least one of the left image and the right imageused a filter to perform sampling.

The 3D content may include a based layer image and at least one extended(or enhanced) layer image, and the image of each layer may be assignedwith a different packet identifier (PID).

Furthermore, the decoding unit may decode the based layer image byreferring to the based layer image, and the decoding unit may decode theextended layer image by referring to the based layer image and the atleast one extended layer image.

In another aspect of the present invention, a data processing method ofa receiving system includes receiving a broadcast signal including a 3Dcontent and system information associated with the 3D content,extracting identification information from the system information,wherein the identification information can identify that the broadcastsignal being received includes the 3D content, decoding the received 3Dcontent based upon transmission format information of the 3D content,and displaying the decoded 3D content as a 3D image based upon a displaymethod of a display device.

It is to be understood that both the foregoing general description andthe following detailed description of the present invention areexemplary and explanatory and are intended to provide furtherexplanation of the invention as claimed.

Advantageous Effects

The receiving system and the method of processing data have thefollowing advantages. When transmitting a 3D content afterdifferentiating (or identifying) an based layer image and at least oneextended layer image of the 3D content, by assigning different packetidentifiers (PIDs) for the image of each layer and transmitting thePID-assigned images, the receiving system is capable of accuratelyidentifying the based layer image and the at least one extended layerimage based upon the PID.

Also, when using a receiving system that cannot process 3D images, sincethe receiving system is incapable of recognizing the PID assigned to theextended layer, the conventional receiving system may disregard thereception of the 3D image. Thus, the present invention can be compatibleto the conventional receiving system.

Furthermore, by enabling additional information, which is required foridentifying and decoding 3D contents, to be acquired by using theidentification information included in the system information, the 3Dcontent may be accurately decoded and displayed.

BRIEF DESCRIPTION OF DRAWINGS

The accompanying drawings, which are included to provide a furtherunderstanding of the invention and are incorporated in and constitute apart of this application, illustrate embodiment(s) of the invention andtogether with the description serve to explain the principle of theinvention. In the drawings:

FIG. 1 illustrates examples of a single video stream format amongmultiple transmission formats for 3D images according to the presentinvention;

FIG. 2 illustrates examples of a multi-video stream format amongmultiple transmission formats for 3D images according to the presentinvention;

FIG. 3 illustrates a PMT syntax structure including identificationinformation in a descriptor format according to an embodiment of thepresent invention, wherein the identification information may recognizethe reception of a 3D image;

FIG. 4 illustrates a syntax structure of an image format descriptoraccording to an embodiment of the present invention;

FIG. 5 illustrates a syntax structure of a view descriptor beingincluded and received in the PMT according to an embodiment of thepresent invention;

FIG. 6 illustrates a flow chart showing the process steps of a receivingsystem for processing 3D images by using the PMT among diverse systeminformation according to the present invention;

FIG. 7 illustrates a VCT syntax structure including identificationinformation in a descriptor format according to an embodiment of thepresent invention, wherein the identification information may recognizethe reception of a 3D image;

FIG. 8 illustrates a syntax structure of a view descriptor beingincluded and received in the VCT according to an embodiment of thepresent invention;

FIG. 9 illustrates a flow chart showing the process steps of a receivingsystem for processing 3D images by using the VCT among diverse systeminformation according to the present invention;

FIG. 10 illustrates a general diagram of a 3D imaging system accordingto an embodiment of the present invention;

FIG. 11 illustrates a block diagram showing a structure of a receivingsystem configured of a decoding device detachably fixed to a displaydevice according to an embodiment of the present invention; and

FIG. 12 illustrates a block diagram showing a structure of a receivingsystem configured of a decoding device non-separably fixed to a displaydevice according to an embodiment of the present invention.

BEST MODE FOR CARRYING OUT THE INVENTION

Reference will now be made in detail to the preferred embodiments of thepresent invention, examples of which are illustrated in the accompanyingdrawings. Wherever possible, the same reference numbers will be usedthroughout the drawings to refer to the same or like parts. In addition,although the terms used in the present invention are selected fromgenerally known and used terms, some of the terms mentioned in thedescription of the present invention have been selected by the applicantat his or her discretion, the detailed meanings of which are describedin relevant parts of the description herein. Furthermore, it is requiredthat the present invention is understood, not simply by the actual termsused but by the meaning of each term lying within.

The present invention relates to having a receiving system capable ofprocessing 3D images to receive and process a 3D image, by enabling thereceiving system to recognize the reception of the 3D image.

The present invention also relates to preventing malfunction in areceiving system incapable of processing 3D images by enabling thereceiving system to disregard the reception of any 3D image.

Herein, 3D images may include stereo (or stereoscopic) images, whichtake into consideration two different perspectives (or viewpoints), andmulti-view images, which take into consideration three differentperspectives.

A stereo image refers to a pair of left-view and right view imagesacquired by photographing the same subject with a left-side camera and aright-side camera, wherein both cameras are spaced apart from oneanother at a predetermined distance. Furthermore, a multi-view imagerefers to a set of at least 3 images acquired by photographing the samesubject with at least 3 different cameras either spaced apart from oneanother at predetermined distances or placed at different angles.

The transmission formats of stereo images include a single video streamformat and a multi-video stream format.

Herein, the single video stream format includes a side-by-side formatshown in (a) of FIG. 1, a top/bottom format shown in (b) of FIG. 1, aninterlaced format shown in (c) of FIG. 1, a frame sequential formatshown in (d) of FIG. 1, a checker board format shown in (e) of FIG. 1,and an anaglyph format shown in (f) of FIG. 1. Also, the multi-videostream format includes a full left/right format shown in (a) of FIG. 2,a full left/half right format shown in (b) of FIG. 2, and a 2Dvideo/depth format shown in (c) of FIG. 2.

For example, the side-by-side format shown in (a) of FIG. 1 correspondsto a case where a left image and a right image are ½ sub-sampled in ahorizontal direction. Herein, the sampled left image is positioned onthe left side, and the sampled right image is positioned on the rightside, thereby creating a single stereo image. The top/bottom formatshown in (b) of FIG. 1 corresponds to a case where a left image and aright image are ½ sub-sampled in a vertical direction. Herein, thesampled left image is positioned on the upper side, and the sampledright image is positioned on the lower side, thereby creating a singlestereo image.

The interlaced format shown in (c) of FIG. 1 corresponds to a case wherea left image and a right image are ½ sub-sampled in a horizontaldirection. Herein, pixels of the sampled left image and pixels of thesampled right image are alternated line by line, thereby creating asingle stereo image. Alternatively, a left image and a right image are ½sub-sampled in a horizontal direction, and pixels of the sampled leftimage and pixels of the sampled right image are alternated pixel bypixel (i.e., in single pixel units), thereby creating a single stereoimage. The checker board format shown in (e) of FIG. 1 corresponds to acase where a left image and a right image are ½ sub-sampled in bothhorizontal and vertical directions. Herein, pixels of the sampled leftimage and pixels of the sampled right image are alternated in singlepixel units, thereby creating a single stereo image.

Furthermore, the full left/right format shown in (a) of FIG. 2corresponds to a case where a left image and a right image aresequentially transmitted. The full left/half right format shown in (b)of FIG. 2 corresponds to a case where the left image remains in itsoriginal state, and where the right image is ½ sub-sampled either in ahorizontal direction or in a vertical direction. Finally, the 2Dvideo/depth format shown in (c) of FIG. 2 corresponds to a case whereone of the left image and the right image is transmitted, and wheredepth information for creating another image is also transmitted at thesame time.

At this point, the stereo image or the multi-view image is compressionencoded in MPEG format or by using diverse methods, thereby beingtransmitted to the receiving system.

For example, a stereo image of the side-by-side format, the top/bottomformat, the interlaced format, the frame sequential format, the checkerboard format, and the anaglyph format may be compression-encoded byusing the H.264/AVC (Advanced Video Coding) method, so as to betransmitted. At this point, the receiving system performs a decodingprocess on the stereo image as an inverse process for the H.264/AVCmethod, thereby acquiring a 3D image.

Furthermore, the left image of the full left/half right format and anyone of the multi-view image may be allocated as a based layer image, andthe remaining image may be allocated as an extended (or enhanced) layerimage. Thereafter, the image of the based layer may be encoded by usingthe same method used for encoding a monoscopic image. And, in the imageof the extended layer, only the correlation information between thebased layer image and the extended layer image may be encoded.Subsequently, the processed images may be transmitted. Examples of thecompression-encoding methods for the based layer image may include JPEG,MPEG-1, MPEG-2, MPEG-4, and H.264/AVC. And, in this embodiment of thepresent invention, the H.264/AVC method has been adopted. Furthermore,according to the embodiment of the present invention, a H.264/MVC(Multi-view Video Coding) method has also been adopted for thecompression-encoding process of the extended layer image.

At this point, the stereo image is allocated to a based layer image anda single extended layer image. However, the multi-view image isallocated to a single based layer image and multiple extended layerimages. The standard for identifying (or differentiating) the multi-viewimage as the based layer image and at least one extended layer image mayeither be decided based upon the position of each camera or be decidedbased upon an alignment form of the camera (or cameras). Furthermore,the standard may also be decided arbitrarily without following anyspecific standard. Herein, the based layer image may also be referred toas a base view, and the extended layer image may also be referred to asa non-base view.

More specifically, when a reference picture is required forcompression-encoding, the based layer image refers to at least one ofthe pictures of the based layer so as to perform compression-encoding.For example, in case of picture B of the based layer, reference is madeto at least one of picture I, picture P, and picture B of the basedlayer so as to perform compression-encoding. Furthermore, when areference picture is required for compression-encoding, the extendedlayer image refers to at least one of the pictures of the based layer soas to perform compression-encoding. At this point, further reference maybe made to pictures of the corresponding extended layer or to picturesof another extended layer, thereby performing compression-encoding. Forexample, when a multi-view image is divided into a based layer image, animage of the first extended layer, and an image of the second extendedlayer, each of the based layer and the first and second extended layerscorresponds to a different view (or viewpoint).

As described above, when the based layer image is compression-encoded byusing the H.264/AVC method, and when the extended layer image iscompression-encoded by using the H.264/MVC method, thereby beingreceived, the receiving system may perform a decoding process on thebased layer image by using only the based layer pictures. Conversely,the extended layer image cannot be decoded by using only the extendedlayer pictures. More specifically, without information on the basedlayer image, the extended layer image cannot be normally decoded.

At this point, when the receiving system decoded only the based layerimage, a general (or regular) 2D image may be acquired. And, when thebased layer image and at least one extended layer image are collectivelydecoded, a 3D image may be acquired.

Therefore, in case of a receiving system that can process 3D images, thereceiving system should be capable of recognizing the reception of a 3Dimage. Also, since a 3D image may be transmitted in diverse formats, thereceiving system should also be informed of the transmission format ofthe corresponding 3D image that is being received, in order to decodethe compression-encoded 3D image to its initial state. Furthermore, areceiving system incapable of processing 3D images should be disregardedthe reception of any 3D image.

Accordingly, by enabling the receiving system that can process 3D imagesto recognize the reception of a 3D image, the present invention canenable the receiving system to receive and process 3D images.

The present invention also relates to preventing malfunction in areceiving system incapable of processing 3D images, by enabling thereceiving system to disregard the reception of any 3D image.

According to an embodiment of the present invention, in a receivingsystem that can process 3D images, identification information enablingthe receiving system to recognize the reception of a 3D image isincluded in the system information, thereby being received by thereceiving system. In some cases, the system information may also bereferred to as service information. Herein, the system information mayinclude channel information, program information, event information, andso on.

According to the embodiment of the present invention, a program specificinformation/program and system information protocol (PSI/PSIP) isadopted as the system information. However, the present invention willnot be limited only to this example. In other words, any protocol thattransmits system information in a table format may be applied in thepresent invention regardless of the name of the corresponding protocol.

The PSI table is an MPEG-2 system standard defined for dividing (orcategorizing) channels and programs. The PSIP table is an advancedtelevision systems committee (ATSC) standard that can enable thedivision (or identification or categorization) of the channels and theprograms. According to an embodiment of the present invention, the PSItable may include a program association table (PAT), a conditionalaccess table (CAT), a program map table (PMT), and a network informationtable (NIT).

Herein, the PAT corresponds to special information that is transmittedby a data packet having a PID of ‘0’. The PAT transmits PID informationof the corresponding PMT and PID information of the corresponding NITfor each program. The CAT transmits information on a paid broadcastingsystem used by a transmitting system. The PMT transmits PID informationof a transport stream (TS) packet, in which program identificationnumbers and individual bit sequences of video and audio data configuringthe corresponding program are transmitted, and also transmits the PIDinformation in which PCR is transmitted. The NIT transmits informationof the actual transmission network. For example, by parsing a PAT tablehaving the PID of ‘0’, a program number and a PID of the PMT may befound (or acquired). Then, by parsing the PMT acquired from the PAT, thecorrelation between the elements configuring the corresponding programmay also be acquired (or found).

According to an embodiment of the present invention, the PSIP table mayinclude a virtual channel table (VCT), a system time table (STT), arating region table (RRT), an extended text table (ETT), a directchannel change table (DCCT), an event information table (EIT), and amaster guide table (MGT).

The VCT transmits information on virtual channels, such as channelinformation for selecting channels and information such as packetidentification (PID) numbers for receiving the audio and/or video data.More specifically, when the VCT is parsed, the PID of the audio/videodata of the broadcast program may be known. Herein, the correspondingaudio/video data are transmitted within the channel along with thechannel name and channel number. The STT transmits information on thecurrent data and timing information. The RRT transmits information onregion and consultation organs for program ratings. The ETT transmitsadditional description of a specific channel and broadcast program. TheEIT transmits information on virtual channel events (e.g., programtitle, program start time, etc.). The DCCT/DCCSCT transmits informationassociated with automatic (or direct) channel change. And, the MGTtransmits the versions and PID information of the above-mentioned tablesincluded in the PSIP.

According to an embodiment of the present invention, the identificationinformation for recognizing the reception of a 3D image is included andreceived in the system information in at least one descriptor format orfield format.

According to an embodiment of the present invention, the identificationinformation is included and received in the PMT of the systeminformation in a descriptor format.

According to another embodiment of the present invention, theidentification information is included and received in the VCT of thesystem information in a descriptor format.

Herein, the identification information may include at least one or moreinformation associated with 3D images. More specifically, theidentification information may include 3D image format type information,view (or viewpoint) identification information, a number of viewsreferred to for the decoding process, and sampling time differenceinformation between the views.

FIG. 3 illustrates a PMT syntax structure including identificationinformation in a descriptor format according to an embodiment of thepresent invention, wherein the identification information can recognizethe reception of a 3D image.

Referring to FIG. 3, a table_id field corresponds to a table identifier.Herein, an identifier that identifies the PMT may be set as the table_idfield.

A section_syntax_indicator field corresponds to an indicator defining asection format of the PMT.

A section_length field indicates the section length of the PMT.

A program_number field corresponds to information matching with the PAT.Herein, the program_number field indicates the number of thecorresponding program.

A version_number field indicates a version number of the PMT.

A current_next_indicator field corresponds to an indicator indicatingwhether the current table section is applicable or not.

A section_number field indicates the section number of the current PMTsection, when the PMT is divided into at least one or more sections,thereby being transmitted.

A last_section_number field indicates the last section number of thecorresponding PMT.

A PCR_PID field indicates the PID of a packet that delivers a programclock reference (PCR) of the current program.

A program_info_length field indicates length information of a descriptorimmediately following the program_info_length field in number of bytes.More specifically, the program_info_length field indicates the length ofeach descriptor included in a first loop.

A stream_type field indicates a type of element stream and encodinginformation included in a packet having the PID value marked in anelementary_PID field that follows.

The elementary_PID field indicates an identifier of the element stream,i.e., the PID value of a packet including the corresponding elementstream.

An ES_info_length field indicates the length information of a descriptorimmediately following the ES_info_length field in number of bytes. Morespecifically, the ES_info_length field indicates the length of eachdescriptor included in a second loop.

According to the present invention, descriptors of a program level areincluded in the descriptor( ) region within the first loop of the PMT,and descriptors of a stream level are included in the descriptor( )region within the second loop of the PMT. More specifically, thedescriptors included in the first loop correspond to descriptors thatare individually applied to each program, and the descriptors includedin the second loop correspond to descriptors that are individuallyapplied to each ES.

According to an embodiment of the present invention, when a programcorresponding to the program_number field value of the PMT is a 3Dcontent, an identification information, which is capable of identifying(or verifying) the reception of a 3D image, is included in thedescriptor( ) region of the first loop in a descriptor format. In thedescription of the present invention, this descriptor will be referredto as an image format descriptor ImageFormat_descriptor( ).

More specifically, when the image format descriptorImageFormat_descriptor( ) is included in the PMT, thereby beingreceived, the receiving system determines that the program correspondingto the program information of the PMT is a 3D content.

FIG. 4 illustrates a syntax structure of an image format descriptorImageFormat_descriptor( ) according to an embodiment of the presentinvention.

A descriptor_tag field indicates that the corresponding descriptor isthe ImageFormat_descriptor( ).

A descriptor_length field indicates the byte size (or length) startingfrom after the descriptor_length field to the end of the descriptorImageFormat_descriptor( ).

A 3D_Image_format_type field indicates by which transmission format thecorresponding 3D content has been received.

Herein, the 3D_Image_format_type field indicates by which of thetransmission formats, i.e., the side-by-side format, the top/bottomformat, the interlaced format, the frame sequential format, the checkerboard format, the anaglyph format, the full left/right format, the fullleft/half right format, and the 2D video/depth format, the corresponding3D image has been received. For example, when the image formatdescriptor ImageFormat_descriptor( ) is included in the PMT and thereceived, the receiving system determines that the program correspondingto the program information of the PMT is a 3D content. Thereafter, whenthe 3D_Image_format_type field value of the ImageFormat_descriptor( ) isequal to ‘001’, the receiving system may determines that thecorresponding 3D content has been received in a side-by-side format.

An LR_first_flag field indicates, when generating a stereo image (orwhen multiplexing a stereo image), whether the uppermost pixel of thefurthermost left side of the frame belongs to the left image, or whetherthe uppermost pixel of the furthermost left side of the frame belongs tothe right image. More specifically, the LR_first_flag field indicateswhether to display the furthermost left side of the received frame asthe left image, or whether to display the furthermost left side of thereceived frame as the right image. According to an embodiment of thepresent invention, if the value of the LR_first_flag field is equal to‘0’, the furthermost left side of the frame is displayed as the leftimage. And, if the value of the LR_first_flag field is equal to ‘1’, thefurthermost left side of the frame is displayed as the right image.

For example, when the transmission format is a side-by-side format, andif the value of the LR_first_flag field is equal to ‘0’, the receivingsystem decodes the pixels of the left-side half of a frame and displaysthe decoded pixels as the left image. And, the receiving system decodesthe pixels of the right-side half of the frame and displays the decodedpixels as the right image. Conversely, when the transmission format is aside-by-side format, and if the value of the LR_first_flag field isequal to ‘1’, the receiving system decodes the pixels of the left-sidehalf of a frame and displays the decoded pixels as the right image. And,the receiving system decodes the pixels of the right-side half of theframe and displays the decoded pixels as the left image.

As another example, when the transmission format is a top/bottom format,and if the value of the LR_first_flag field is equal to ‘0’, thereceiving system decodes the pixels of the upper half of a frame anddisplays the decoded pixels as the left image. And, the receiving systemdecodes the pixels of the lower half of the frame and displays thedecoded pixels as the right image. Conversely, when the transmissionformat is a top/bottom format, and if the value of the LR_first_flagfield is equal to ‘1’, the receiving system decodes the pixels of theupper half of a frame and displays the decoded pixels as the rightimage. And, the receiving system decodes the pixels of the lower half ofthe frame and displays the decoded pixels as the left image.

A spatial_flipping_flag field indicates whether at least one of the leftimage and the right image is inversely scanned and encoded. When thetransmitting system encodes a stereo image consisting of a left imageand a right image, the transmitting system scans the image by inversing(or flipping) the scanning direction of at least one of the left andright images, so as to enhance the coding efficiency. More specifically,depending upon the scanning efficiency, inverse scanning (or alignment)may be performed on the left or right image in a vertical or horizontaldirection. The inversely-scanned images will hereinafter be referred toas mirrored images for simplicity.

According to an embodiment of the present invention, when thetransmission format is a side-by-side format, the present inventionperforms inverse scanning on the left or right image in a horizontaldirection, thereby encoding the inversely-scanned image. And, when thetransmission format is a top/bottom format, the present inventionperforms inverse scanning on the left or right image in a verticaldirection, thereby encoding the inversely-scanned image. According tothe embodiment of the present invention, in this case, thespatial_flipping_flag field is marked to have the value of ‘1’. If thespatial_flipping_flag field value is equal to ‘1’, prior to displayingthe mirrored images, the receivined system inversely aligns the mirroredimages in the initial (or original) scanning order, thereby displayingthe aligned images. On the other hand, when the spatial_flipping_flagfield value is equal to ‘0’, this indicates that the pixels of the leftand right image are aligned in the initial scanning order, thereby beingencoded.

When the spatial_flipping_flag field value is equal to ‘1’, animage0_flipped_flag field indicates which image has been flipped (ormirrored or inverted). According to the embodiment of the presentinvention, if image0 is flipped, then the image0_flipped_flag fieldvalue is equal to ‘1’. And, if image1 is flipped, theimage0_flipped_flag field is equal to ‘0’. Herein, image0 corresponds toan image having the uppermost pixel of the furthermost left side of aframe, which consists of left and right images, belonging thereto. And,image1 corresponds to the other image. More specifically, the mappingrelation between image0 and image1 and the left or right image is setbased upon the LR_first_flag field. If the LR_first_flag field is equalto ‘0’, the left image corresponds to image0 and the right imagecorresponds to image1.

A quincunx_filtering_flag field indicates whether a quincunx filter hasbeen used to perform sampling, when generating the stereo image.According to an embodiment of the present invention, when thetransmitting system samples a left image or a right image to ahalf-resolution image, and if the quincunx filter has been used for thesampling process, the quincunx_filtering_flag field is marked to havethe value of ‘1’. Otherwise, the quincunx_filtering_flag field is markedto have the value of ‘0’. Herein, if the quincunx_filtering_flag fieldis equal to ‘1’, the receiving system performs an inverse process ofquincunx filtering on the corresponding image. For example, in case ofthe side-by-side format, the top/bottom format, and the full left/halfright format, when ½-sub-sampling the left or right image in ahorizontal or vertical direction, and if the quincunx filter has beenused, the quincunx_filtering_flag field is marked to have the value of‘1’. According to another embodiment of the present invention, in caseof the side-by-side format, the top/bottom format, and the fullleft/half right format, when ½-sub-sampling the left or right image in ahorizontal or vertical direction, a filter other than the quincunxfilter may be used. For this case, the present invention may furtherinclude a field indicating the type of filter used herein.

As described above, when the receiving system recognizes the imageformat descriptor, and when the receiving system supports thetransmission format indicated by the value of the 3D_image_format_typefield within the image format descriptor, the corresponding 3D contentmay be decoded by referring to other fields included in the image formatdescriptor. Meanwhile, in case of the conventional receiving system thatis incapable of processing 3D images, since the receiving system isunable to recognize the image format descriptor, the correspondingreceiving system can perform decoding only on 2D images. For example, ifan image format descriptor is not included in a PMT that is beingreceived, the corresponding ES may be decoded by using the same methodas the conventional method for decoding 2D images.

Moreover, according to an embodiment of the present invention, when itis assumed that a 3D image is transmitted by being divided into a basedlayer image and at least one extended layer image (i.e., a non-base viewimage), different packet identifiers (PIDs) are allocated to each layer,thereby configuring respective elementary streams (ESs), which are thentransmitted.

For example, when it is assumed that a 3D image is divided into a basedlayer, a first extended layer, and a second extended layer, the PIDvalue being inserted in the header of a stream packet including the ESof the based layer, the PID value being inserted in the header of astream packet including the ES of the first extended layer, and the PIDvalue being inserted in the header of a stream packet including the ESof the second extended layer are different from one another. Morespecifically, different PIDs are allocated for each view (or viewpoint).

According to the embodiment of the present invention, the stream packetis configured of a header and a payload. Herein, the header is assignedwith 4 bytes, and the payload is assigned with 184 bytes. Since thenumber of bytes that are to be assigned to the header and payload of thestream packet may vary depending upon the design of the system designer,the present invention will not be limited only to the exemplary numbersgiven in the description of the present invention set forth herein.

Furthermore, according to an embodiment of the present invention, whenthe based layer (i.e., base view) image is compression-encoded by usingthe H.264/AVC method, it is indicated in the value of the stream_typefield corresponding to the ES of the based layer, that the respective EShas been compression-encoded by using the H.264/AVC method. Also, whenthe extended layer (i.e., non-base view) image is compression-encoded byusing the H.264/MVC method, it is indicated in the value of thestream_type field corresponding to the ES of the extended layer, thatthe respective ES has been compression-encoded by using the H.264/MVCmethod.

According to an embodiment of the present invention, the stream_typefield corresponding to the ES of the based layer is assigned with thevalue of ‘0xB1’, and the stream_type field corresponding to the ES ofthe extended layer is assigned with a value other than ‘0xB1’, such as‘0xB2’.

In this case, by parsing the stream_type field, the receiving system mayacquire encoding information of the corresponding ES. And, by referringto the acquired encoding information, the receiving system may perform adecoding process on the corresponding ES.

Additionally, according to an embodiment of the present invention, whenthe 3D image is divided into a based layer image and an extended layerimage, and when the image of the extended layer has beencompression-encoded by using the H.264/MVC method, a view (or viewpoint)information required for decoding the extended layer image is includedin the second loop of the PMT in a field format or a descriptor format,thereby being received.

Herein, the view information may include identification information thatcan identify (or differentiate) each view (or viewpoint), and referenceview identification information required for decoding the EScorresponding to current view.

According to the embodiment of the present invention, the viewinformation is included in the second loop of the PMT in a descriptorformat, thereby being received. In the description of the presentinvention, this descriptor will be referred to as a view descriptorPMT_view_descriptor( ) for simplicity. In this case, the view descriptorPMT_view_descriptor( ) is individually applied to each ES.

More specifically, when the view descriptor is included and received inthe PMT, the receiving system may acquire view information required fordecoding the corresponding ES.

FIG. 5 illustrates a syntax structure of a view descriptorPMT_view_descriptor( ) being included and received in the PMT accordingto an embodiment of the present invention.

A descriptor_tag field indicates that the corresponding descriptor isthe PMT_view_descriptor( ).

A descriptor_length field indicates the byte size (or length) startingfrom after the descriptor_length field to the end of the descriptorPMT_view_descriptor( ).

A view_id field indicates view identification information (i.e., viewid) of an ES that is being delivered through the corresponding PID.

A number_of_reference_view field indicates a number of views that hadbeen referred to when encoding was performed on the image of the viewcorresponding to the view_id field.

A reference_view_id field indicates identification information of viewsthat had been repeatedly referred to, as many times as thenumber_of_reference_view field value, when encoding was performed on theimage of the view corresponding to the view_id field.

More specifically, in order to decode the extended layer image by usingthe H.264/MVC method, the ES of the corresponding view as well as the ESof a different view may be required. In order to do so, thenumber_of_reference_view field transmits the number of referred views,and the reference_view_id field transmits view identificationinformation corresponding to the number of views that are repeatedlyreferred to as many times as the number_of_reference_view field value.

A time_difference_between_base_view field indicates a sampling timedifference that may occur between views. For example, if the displaymethod is a shutter glass method, the 3D image is realized bysequentially displaying the left image and the right image. At thispoint, a difference may occur between the sampling time for the left andright images and the time both left and right images are recognized (oridentified) by the human eyes. Thus, a distortion may occur due to achange in depth with the eye when the image is moving. Therefore, thepresent invention uses the time_difference_between_base_view field toindicate the difference in sampling time that may occur between views.The value of the time_difference_between_base_view field may be used bythe receiving system to compensate the above-described distortion.

If the image of a view corresponding to the view_id field correspondingto a based layer image, the value of the number_of_reference_view fieldand the value of the time_difference_between_base_view field are markedas ‘0’.

The order, position, and definition of the fields allocated to the viewdescriptor PMT_view_descriptor( ), shown in FIG. 5, are merely examplespresented to facilitate and simplify the understanding of the presentinvention. In other words, the order, position, and definition of thefields allocated to the view descriptor PMT_view_descriptor( ) and thenumber of fields that can be additionally allocated thereto may beeasily altered or modified by the system designer. Therefore, thepresent invention will not be limited to the examples given in theabove-described embodiment of the present invention.

FIG. 6 illustrates a flow chart showing the process steps of a receivingsystem for processing 3D images by using the PMT among diverse systeminformation according to the present invention. For example, in case ofa 3D image, it is assumed that the 3D image is divided intro a basedlayer and at least one extended layer each having a PID different fromone another. Herein, it is also assumed that the extended layer image iscompression-encoded by using the H.264/MVC method, thereby beingreceived.

More specifically, in order to provide 3D image service, the receivingsystem finds a PAT having a PID of ‘0’ (i.e., PID=0) from an inputtedbit stream (S401). Then, the receiving system acquires a PID of the PMTfrom the PAT and gathers (or collects) stream packets having theacquired PIDs of the PMT, thereby configuring the PMT (S402).Subsequently, the PMT is parsed (S403), so that the receiving system canverify whether or not the image format descriptorImageFormat_descriptor( ) is included and received in the first loop ofthe descriptor( ) within the PMT (S404).

At this point, when the image format descriptor ImageFormat_descriptor() is detected from the PMT, the receiving system determines that theprogram corresponding to the program number of the PMT is a 3D content.If the image format descriptor ImageFormat_descriptor( ) is not detectedfrom the PMT, the receiving system determines that the programcorresponding to the program number of the PMT is a 2D content. When itis determined in step 404 that the corresponding program is a 2Dcontent, the receiving system uses the corresponding ES information ofthe second loop within the PMT, so as to extract the PID correspondingto the 2D content (S411). Subsequently, the receiving system performsdecoding on the stream packets corresponding to the extracted PID(S412). According to an embodiment of the present invention, the 2Dcontent is compression-decoded by using an inverse method of theH.264/AVC compression-encoding method.

The 2D content decoded in step 412 is displayed on the display device asa 2D image (S413).

Meanwhile, when it is determined in step 404 that the correspondingprogram is a 3D content, the receiving system sets up a configurationfor the display based upon the fields included in the image formatdescriptor (S405). Then, the receiving system extracts a PIDcorresponding to the ES of the based layer in the second loop of the PMT(S406). Subsequently, the receiving system performs decoding on thestream packets corresponding to the extracted PID, thereby recoveringthe initial (or original) image (S407). For example, if the based layerimage was the left image, after the decoding process, the correspondingimage is recovered to the left image prior to being processed withcompression-encoding. According to an embodiment of the presentinvention, the ES of the based layer is decoded as an inverse method ofthe H.264/AVC compression-encoding method.

Subsequently, the receiving system extracts a PID corresponding to theES of the extended layer from the second loop of the PMT (S408).Thereafter, the receiving system performs decoding on the stream packetscorresponding to the extracted PID, thereby recovering the initial (ororiginal) image (S409). For example, if the extended layer image was theright image, after the decoding process, the corresponding image isrecovered to the right image prior to being processed withcompression-encoding. According to an embodiment of the presentinvention, the ES of the extended layer is decoded as an inverse methodof the H.264/MVC compression-encoding method.

If the 3D image has multiple extended layers due to being a multi-viewimage, step 408 and step 409 are repeated as many times as the number ofextended layers, thereby recovering the image of all extended layers. Atthis point, when the view descriptor is included in the PMT, thereceiving system refers to the view information acquired by parsing theview descriptor, thereby being capable of decoding the extended layerimage.

When the based layer image is recovered by processing step 407, and whenthe extended layer image is recovered by processing step 409, therecovered based layer image and at least one of the recovered extendedlayer image are used so as to display the 3D image on the display devicein accordance with the respective display method (S410). Morespecifically, by using at least two images based upon thecharacteristics of the display device, the receiving system creates anddisplays a 3D image using a variety of methods. For example, the displaymethod may include a method of wearing special glasses, and a method ofnot wearing any glasses.

The method of wearing special glasses is then divided intro a passivemethod and an active method. The passive method corresponds to a methodof showing the 3D image by differentiating the left image and the rightimage using a polarizing filter. More specifically, the passive methodcorresponds to a method of wearing a pair of glasses with one red lensand one blue lens fitted to each eye, respectively. The active methodcorresponds to a method of differentiating the left image and the rightimage by sequentially covering the left eye and the right eye at apredetermined time interval. More specifically, the active methodcorresponds to a method of periodically repeating a time-split (ortime-divided) and viewing the corresponding image through a pair ofglasses equipped with electronic shutters which are synchronized withthe time-split cycle period of the image. The active method may also bereferred to as a time-split method or a shuttered glass method.

The most well-known methods of not wearing any glasses include alenticular method and a parallax barrier method. Herein, the lenticularmethod corresponds to a method of fixing a lenticular lens panel infront of an image panel, wherein the lenticular lens panel is configuredof a cylindrical lens array being vertically aligned. The parallaxmethod corresponds to a method of providing a barrier layer havingperiodic slits above the image panel. Meanwhile, the identificationinformation that can recognize the reception of 3D images according tothe present invention (i.e., the image format descriptor shown in FIG.4) may be included in the VCT, thereby being received.

FIG. 7 illustrates a VCT syntax structure including identificationinformation in a descriptor format according to an embodiment of thepresent invention, wherein the identification information may recognizethe reception of a 3D image.

Referring to FIG. 7, a table_id field corresponds to a table identifier.Herein, an identifier that identifies the VCT may be set as the table_idfield.

A section_syntax_indicator field corresponds to an indicator defining asection format of the VCT.

A section_length field indicates the section length of the VCT.

A transport_stream_id field is identical to a transport stream IDincluded in a program association table (PAT) having a PID value of ‘0’.

A version_number field indicates a version number of the VCT.

A current_next_indicator field corresponds to an indicator indicatingwhether the current table section is applicable or not.

A section_number field indicates the section number of the current VCTsection, when the VCT is divided into at least one or more sections,thereby being transmitted.

A last_section_number field indicates the last section number of thecorresponding VCT. And, a num_channels_in_section field designates atotal number of virtual channels existing in the VCT section.

The VCT syntax further includes a first repetition statement, ‘for’ loopwhich is repeated as many times as the num_channels_in_section fieldvalue. The first repetition statement may include a short_name field, amajor_channel_number field, a minor_channel_number field, amodulation_mode field, a carrier_frequency field, a channel_TSID field,a program_number field, an ETM_location field, an access_controlledfield, a hidden field, a service_type field, a source_id field, adescriptor_length field, and a second repetition statement, ‘for’ loopwhich is repeated as many times as the number of descriptors included inthe first repetition statement. In the description of the presentinvention, the second repetition statement will be referred to as afirst descriptor loop for simplicity. The descriptor descriptors( )included in the first descriptor loop is separately applied to eachvirtual channel.

In the first repetition statement, the short_name field indicates thename of a virtual channel. The major_channel_number field indicates a‘major’ channel number associated with the virtual channel definedwithin the first repetition statement, and the minor_channel_numberfield indicates a ‘minor’ channel number. More specifically, each of thechannel numbers should be connected to the major and minor channelnumbers, and the major and minor channel numbers are used as userreference numbers for the corresponding virtual channel.

The program_number field is shown for connecting the virtual channelhaving an MPEG-2 program association table (PAT) and program map table(PMT) defined therein, and the program_number field matches the programnumber within the PAT/PMT. Herein, the PAT describes the elements of aprogram corresponding to each program number, and the PAT indicates thePID of a transport packet transmitting the PMT. The PMT describessubordinate information and also a PID list of the transport packetthrough which a program identification number and a separate bitsequence, such as video and/or audio data configuring the program, arebeing transmitted.

Furthermore, the VCT syntax may further include anadditional_descriptor_length field, and a third repetition statement,‘for’ loop which is repeated as many times as the number of descriptorsadditionally added to the VCT. In the description of the presentinvention, the third repetition statement will be referred to as asecond descriptor loop for simplicity. The descriptoradditional_descriptors( ) included in the second descriptor loop iscommonly applied to all virtual channels described in the VCT.

The image format descriptor according to the present invention may beincluded in the first descriptor loop of the VCT shown in FIG. 7.

When the program corresponding to the program_number field value of theVCT is a 3D content, the present invention may include and transmit animage format descriptor, which can verify that a 3D image is beingreceived, in a descriptor( ) region of the first descriptor loopincluded in the VCT. According to an embodiment of the presentinvention, the syntax structure of the image format descriptorImageFormat_descriptor( ) and the description of each field areidentical as those shown in FIG. 4.

For example, when the image format descriptor is included and receivedin the VCT, the receiving system determines that the programcorresponding to the program information of the VCT is a 3D content.Also, when the value of the 3D_Image_format_type field within the imageformat descriptor is equal to ‘001’, the receiving system may determinethat the corresponding 3D content is being received in the side-by-sideformat.

More specifically, when the receiving system recognizes the image formatdescriptor, and when the receiving system supports the transmissionformat designated by the value of the 3D_Image_format_type field withinthe image format descriptor, the receiving system may decode thecorresponding 3D content. Meanwhile, if the receiving system correspondsto the conventional receiving system that is incapable of processing 3Dimages, since the receiving system is unable to recognize the imageformat descriptor, the receiving system may perform decoding only on 2Dimages. For example, if the image format descriptor is not included inthe VCT that is currently being received, the corresponding ES may bedecoded by using the same method for decoding the conventional 2Dcontent.

Furthermore, according to an embodiment of the present invention, whenthe 3D image is divided into a based layer image and an extended layerimage, and when the extended layer image is encoded by using theH.264/MVC method, a view information required for decoding the extendedlayer image is included and received in the first descriptor loop of theVCT in a descriptor format.

The view information may include identification information that canidentify (or differentiate) each view (or viewpoint), and reference viewidentification information, which is required for decoding the EScorresponding to the current view.

In the description of the present invention, the above-describeddescriptor will be referred to as a view descriptor VCT_view_descriptor() for simplicity. In this case, the view descriptor is individuallyapplied to each ES. More specifically, if the view descriptor isincluded and received in the VCT, the receiving system may acquire viewinformation required for decoding the corresponding ES.

FIG. 8 illustrates a syntax structure of a view descriptorVCT_view_descriptor( ), which is included and received in the VCTaccording to an embodiment of the present invention.

A descriptor_tag field indicates that the corresponding descriptor isthe VCT_view_descriptor( ).

A descriptor_length field indicates the byte size (or length) startingfrom after the descriptor_length field to the end of the descriptorVCT_view_descriptor( ).

A stream_type field indicates the types of element streams and encodinginformation included in the packet having the PID value marked in theelementary_PID field that follows.

Herein, according to an embodiment of the present invention, when thebased layer (i.e., base view) image is compression-encoded by using theH.264/AVC method, it is indicated in the value of the stream_type fieldcorresponding to the ES of the based layer, that the respective ES hasbeen compression-encoded by using the H.264/AVC method. Also, when theextended layer (i.e., non-base view) image is compression-encoded byusing the H.264/MVC method, it is indicated in the value of thestream_type field corresponding to the ES of the extended layer, thatthe respective ES has been compression-encoded by using the H.264/MVCmethod. In this case, by parsing the stream_type field, the receivingsystem may acquire encoding information of the corresponding ES. And, byreferring to the acquired encoding information, the receiving system mayperform a decoding process on the corresponding ES.

The elementary_PID field indicates an identifier of the element stream,i.e., the PID value of the packet including the corresponding elementstream.

A view_id field indicates view identification information (i.e., viewid) of an ES that is being delivered through the corresponding PID.

A number_of_reference_view field indicates a number of views that hadbeen referred to when encoding was performed on the image of the viewcorresponding to the view_id field.

A reference_view_id field indicates an identification information ofviews that had been repeatedly referred to, as many times as thenumber_of_reference_view field value, when encoding was performed on theimage of the view corresponding to the view_id field. More specifically,in order to decode the extended layer image by using the H.264/MVCmethod, the ES of the corresponding view as well as the ES of adifferent view may be required. In order to do so, thenumber_of_reference_view field transmits the number of referred views,and the reference_view_id field transmits view identificationinformation corresponding to the number of views that are repeatedlyreferred to as many times as the number_of_reference_view field value.

A time_difference_between_base_view field indicates a sampling timedifference that may occur between views. For example, if the displaymethod is a shutter glass method, the 3D image is realized bysequentially displaying the left image and the right image. At thispoint, a difference may occur between the sampling time for the left andright images and the time both left and right images are recognized (oridentified) by the human eyes. Thus, a distortion may occur due to achange in depth with the eye when the image is moving. Therefore, thepresent invention uses the time_difference_between_base_view field toindicate the difference in sampling time that may occur between views.The value of the time_difference_between_base_view field may be used bythe receiving system to compensate the above-described distortion.

If the image of a view corresponding to the view_id field correspondingto a based layer image, the value of the number_of_reference_view fieldand the value of the time_difference_between_base_view field are markedas ‘0’.

The order, position, and definition of the fields allocated to the viewdescriptor VCT_view_descriptor( ), shown in FIG. 8, are merely examplespresented to facilitate and simplify the understanding of the presentinvention. In other words, the order, position, and definition of thefields allocated to the view descriptor VCT_view_descriptor( ) and thenumber of fields that can be additionally allocated thereto may beeasily altered or modified by the system designer. Therefore, thepresent invention will not be limited to the examples given in theabove-described embodiment of the present invention.

FIG. 9 illustrates a flow chart showing the process steps of a receivingsystem for processing 3D images by using the VCT among diverse systeminformation according to the present invention. For example, in case ofa 3D image, it is assumed that the 3D image is divided intro a basedlayer and at least one extended layer each having a PID different fromone another. Herein, it is also assumed that the extended layer image iscompression-encoded by using the H.264/MVC method, thereby beingreceived.

More specifically, in order to provide 3D image service, the receivingsystem configures a VCT from the received stream through a tableidentifier (S701). Then, the receiving system parses the configured VCT(S702). Subsequently, the receiving system verifies whether the imageformat descriptor ImageFormat_descriptor( ) is included and received inthe first descriptor of the VCT (S703).

At this point, when the image format descriptor ImageFormat_descriptor() is detected from the VCT, the receiving system determines that theprogram corresponding to the program number of the VCT is a 3D content.If the image format descriptor ImageFormat_descriptor( ) is not detectedfrom the VCT, the receiving system determines that the programcorresponding to the program number of the VCT is a 2D content. When itis determined in step 703 that the corresponding program is a 2Dcontent, the receiving system uses the corresponding ES information of aservice location descriptor service_location_descriptor( ) within theVCT, so as to extract the PID corresponding to the 2D content (S710).Subsequently, the receiving system performs decoding on the streampackets corresponding to the extracted PID (S711). According to anembodiment of the present invention, the 2D content iscompression-decoded by using an inverse method of the H.264/AVCcompression-encoding method. The 2D content decoded in step 711 isdisplayed on the display device as a 2D image (S712).

Meanwhile, when it is determined in step 703 that the correspondingprogram is a 3D content, the receiving system sets up a configurationfor the display based upon the fields included in the image formatdescriptor (S704). Then, the receiving system extracts a PIDcorresponding to the ES of the based layer in the service locationdescriptor service_location_descriptor( ) of the first descriptor loopwithin the VCT (S705). Subsequently, the receiving system performsdecoding on the stream packets corresponding to the extracted PID,thereby recovering the initial (or original) image (S706). For example,if the based layer image was the left image, after the decoding process,the corresponding image is recovered to the left image prior to beingprocessed with compression-encoding. According to an embodiment of thepresent invention, the ES of the based layer is decoded as an inversemethod of the H.264/AVC compression-encoding method.

Subsequently, the receiving system extracts a PID corresponding to theES of the extended layer from the service location descriptorservice_location_descriptor( ) of the first descriptor loop within theVCT (S707). Thereafter, the receiving system performs decoding on thestream packets corresponding to the extracted PID, thereby recoveringthe initial (or original) image (S708). For example, if the extendedlayer image was the right image, after the decoding process, thecorresponding image is recovered to the right image prior to beingprocessed with compression-encoding. According to an embodiment of thepresent invention, the ES of the extended layer is decoded as an inversemethod of the H.264/MVC compression-encoding method.

If the 3D image has multiple extended layers due to being a multi-viewimage, step 707 and step 708 are repeated as many times as the number ofextended layers, thereby recovering the image of all extended layers. Atthis point, when the view descriptor is included in the VCT, thereceiving system refers to the view information acquired by parsing theview descriptor, thereby being capable of decoding the extended layerimage.

When the based layer image is recovered by processing step 706, and whenthe extended layer image is recovered by processing step 708, therecovered based layer image and at least one of the recovered extendedlayer image are used so as to display the 3D image on the display devicein accordance with the respective display method (S709). Morespecifically, by using at least two images based upon thecharacteristics of the display device, the receiving system creates anddisplays a 3D image using a variety of methods. For example, the displaymethod may include a method of wearing special glasses, and a method ofnot wearing any glasses.

FIG. 10 illustrates a general diagram of a 3D imaging system accordingto an embodiment of the present invention. Herein, the 3D imaging systemmay include a content source, a decoding device, and a display device.The content source includes 3D contents for 3D (or 3-dimensional)imaging. For example, the content source may correspond to a disc, aninternet server, terrestrial/satellite/cable broadcast stations, and soon. The decoding device receives a content from the content source anddecodes the received content, so as to create an image that is to bedisplayed. For example, when the received content iscompression-encoded, the decoding device performs decompression and/orinterpolation processes, thereby recovering the original image. Examplesof the decoding device may include a disc player, an IPTV settop box,and a television (TV) that shows terrestrial, satellite, and cablebroadcast programs.

The display device displays the image created in the decoding device ina 2D or 3D format. Examples of the display device may include a devicethat can display general 2D images, a device that can display 3D imagesrequiring special viewing glasses, and a device that can display 3Dimages without requiring any special viewing glasses.

According to an embodiment of the present invention, when a 3D image isrealized by parsing an image format descriptor and a view descriptorfrom the PMT, process steps excluding step 410 and step 413 areprocessed in the decoding device, and step 410 and step 413 processed inthe display device.

According to another embodiment of the present invention, when a 3Dimage is realized by parsing an image format descriptor and a viewdescriptor from the VCT, process steps excluding step 709 and step 712are processed in the decoding device, and step 709 and step 712 areprocessed in the display device.

For example, it is assumed that the value of the 3D_image_format_typefield acquired from the image format descriptor included in the PMT orVCT indicates the side-by-side transmission format, that theLR_first_flag field value is equal to ‘0’, that thespatial_flipping_flag field value is equal to ‘1’, that theimage0_flipped_flag field value is equal to ‘0’, and that thequincunx_filtering_flag is equal to ‘1’. In this case, it can be knownthat the uppermost pixel of the furthermost left side of the receivedframe belongs to the left image, that the right image has been inverselyscanned during the encoding process, and that a quincunx filter has beenused when sampling the left and right images. Therefore, the decodingdevice scans the right image in an inversed direction and decodes theinversely-scanned image. At this point, the corresponding image isrecovered to its initial image size by being processed with an inverseprocess of the quincunx filter or with an adequate inversed filteringprocess. The display device displays image recovered by decoding theright-side half of the pixels as left image. Also, the display devicedisplays image recovered by decoding the right-side half of the pixelsas the right image.

In the description of the present invention, the decoding device and thedisplay device will be collectively referred to as a receiving systemfor simplicity.

Herein, the receiving system may be configured of the decoding deviceand the display device, both parts being separable (i.e., the decodingdevice being detachably fixed to the display device). Alternatively, thereceiving system may be configured as a single body consisting of thedecoding device and the display device.

FIG. 11 illustrates a block diagram showing a structure of a receivingsystem configured of a decoding device detachably fixed to a displaydevice according to an embodiment of the present invention.

More specifically, the decoding device 810 may include a controller 811,a user interface 812, a receiving unit 813, a demultiplexer 814, asystem information processor 815, an audio decoder 816, and a videodecoder 817. The display device 820 may include a user interface 821, aspeaker 822, and a 2D/3D display unit 823.

A 2D image or 3D image content transmitted from the content source and asystem information required for decoding the 2D image or 3D image arereceived in the receiving unit 813. Then, when a specificreception-requested channel is selected by using the user interface 812,the controller 811 controls the receiving unit 813 so that only the 2Dimage or 3D image of the corresponding channel can be received. At thispoint, in case of the 3D image, a stream corresponding to each view (orviewpoint) is PES-packetized, thereby being received in a TS packetformat having a separate PID. For example, a based layer image and atleast one extended layer image are each assigned with a different PID,thereby being received.

The receiving unit 811 performs demodulation and channel-equalizationprocesses on the 2D image or 3D image of the specific channel, therebyoutputting the processed image to the demultiplexer 814 in a streamformat. The system information received by the receiving unit 811 isalso outputted to the demultiplexer 814 in a stream format.

The demultiplexer 814 refers to the PID of each stream. Then, thedemultiplexer 814 outputs the audio stream to the audio decoder 816 andoutputs the video stream to the video decoder 817. Thereafter, thedemultiplexer 814 outputs the system information to the systeminformation processor 815.

At this point, a system time clock (STC), a decoding time stamp (DTS),and a presentation time stamp (PTS) are multiplexed in the stream beinginputted to the demultiplexer 814. Herein, the decoding time stamp (DTS)indicates when to decode each picture based upon the STC. Thepresentation time stamp (PTS) indicates when to display the decoded databased upon the STC. More specifically, the STC corresponds to an overallclock that is locked with a video encoder of the transmitting system.Herein, the video encoder and the video decoder have the same STC. And,since a video signal is internally delayed in the video encoder, inorder to perform A/V lip-synchronization and a normal video decodingprocess, the video decoder generates a DTS and a PTS based upon the STC,which are then collectively transmitted.

Therefore, for the synchronization between each view (or viewpoint), thedemultiplexer 814 recovers the STC, which is a reference standard forthe DTS and the PTS, from the stream based upon the control of thecontroller 811. Thereafter, the demultiplexer 814 outputs the recoveredSTC to the video decoder 817.

A method identifying reception of a 3D image based upon the PMT will nowbe described as follows.

More specifically, the system information processor 815 finds a PAThaving a PID of ‘0’ (i.e., PID=0) from a system information stream.Then, the system information processor 815 acquires a PID of the PMTfrom the PAT and gathers (or collects) stream packets having theacquired PIDs of the PMT, thereby configuring the PMT. Subsequently, thesystem information processor 815 parses the PMT, so that the systeminformation processor 815 can verify whether or not the image formatdescriptor ImageFormat_descriptor( ) is included and received in thefirst loop of the descriptor( ) within the PMT.

At this point, when the image format descriptor ImageFormat_descriptor() is detected from the PMT, the system information processor 815determines that the program corresponding to the program number of thePMT is a 3D content. Alternatively, if the image format descriptorImageFormat_descriptor( ) is not detected from the PMT, the systeminformation processor 815 determines that the program corresponding tothe program number of the PMT is a 2D content.

Therefore, if the image format descriptor ImageFormat_descriptor( ) isnot detected from the PMT, the system information processor 815 uses theES information corresponding to the second loop of the PMT to extractthe PID corresponding to the 2D content. Subsequently, the systeminformation processor 815 outputs the extracted PID to the demultiplexer814. The demultiplexer 814 respectively outputs the audio stream and thevideo stream, each corresponding to the inputted PID, to the audiodecoder 816 and the video decoder 817.

For example, the video decoder 817 performs decoding, as an inversemethod of the H.264/AVC compression-encoding method, on the inputtedvideo stream, thereby outputting the processed video stream to the 2D/3Ddisplay unit 823. The 2D/3D display unit 823 displays the decoded videostream to the display device as a 2D image.

Meanwhile, when the image format descriptor ImageFormat_descriptor( ) isdetected from the PMT, the system information processor 815 extracts aPID corresponding to the ES of the based layer from the second loop ofthe PMT, thereby outputting the extracted PID to the demultiplexer 814.The demultiplexer 814 respectively outputs the audio stream and thevideo stream, each corresponding to the inputted PID, to the audiodecoder 816 and the video decoder 817.

For example, if the based layer image was the left image, afterperforming a decoding process in the video decoder 817, thecorresponding image is recovered to the left image prior to beingprocessed with compression-encoding. According to an embodiment of thepresent invention, the ES of the based layer is decoded as an inversemethod of the H.264/AVC compression-encoding method.

Furthermore, the system information processor 815 extracts a PIDcorresponding to the ES of the based layer from the second loop of thePMT, thereby outputting the extracted PID to the demultiplexer 814. Thedemultiplexer 814 respectively outputs the audio stream and the videostream, each corresponding to the inputted PID, to the audio decoder 816and the video decoder 817. At this point, the system informationprocessor 815 extracts a PID corresponding to the ES of the based layerfrom the second loop of the PMT, thereby outputting the extracted PID tothe demultiplexer 814. For example, if the extended layer image was theright image, after performing a decoding process in the video decoder817, the corresponding image is recovered to the right image prior tobeing processed with compression-encoding. According to an embodiment ofthe present invention, the ES of the extended layer is decoded as aninverse method of the H.264/MVC compression-encoding method.

If the 3D image has multiple extended layers due to being a multi-viewimage, the system information processor 815 extracts a corresponding PIDas many times as the number of extended layers. Then, by outputting theextracted PIDs to the demultiplexer 814, a multi-view image may berecovered in the video decoder 817. At this point, when the viewdescriptor is included in the PMT, the receiving system refers to theview information acquired by parsing the view descriptor, thereby beingcapable of decoding the extended layer image.

The 2D/3D display unit 823 uses the based layer image and at least oneof the extended layer image recovered in the video decoder 817, so as todisplay the 3D image on the display device in accordance with therespective display method. More specifically, by using at least twoimages based upon the characteristics of the display device, the 2D/3Ddisplay unit 823 creates and displays a 3D image using a variety ofmethods. For example, the display method may include a method of wearingspecial glasses, and a method of not wearing any glasses.

FIG. 12 illustrates a block diagram showing a structure of a receivingsystem configured of a decoding device non-separably fixed to a displaydevice (i.e., the receiving system being configured as a single bodyconsisting of a decoding device and a display device) according to anembodiment of the present invention. The same reference numerals usedfor indicating the blocks having the same structure and functions asthose shown in FIG. 11 will be given to the elements shown in FIG. 12.In this case, since reference may be made to FIG. 11 for the detailedoperation of each block, detailed description of the same will beomitted in FIG. 12 for simplicity.

It will be apparent to those skilled in the art that variousmodifications and variations can be made in the present inventionwithout departing from the spirit or scope of the inventions. Thus, itis intended that the present invention covers the modifications andvariations of this invention provided they come within the scope of theappended claims and their equivalents.

MODE FOR THE INVENTION

Meanwhile, the mode for the embodiment of the present invention isdescribed together with the ‘best Mode’ description.

INDUSTRIAL APPLICABILITY

The embodiments of the method for transmitting and receiving signals andthe apparatus for transmitting and receiving signals according to thepresent invention can be used in the fields of broadcasting andcommunication.

1. A receiving system comprising: a receiving unit for receiving a broadcast signal comprising a program which carries a program element for a 3-dimensional (3D) content and signaling information of the program, the 3D content comprising images of different views; a signaling information processor for processing the signaling information from the broadcast signal; a decoder for decoding the program element for the 3D content; and a displaying unit for displaying the 3D content according to the signaling information, wherein the signaling information includes a first table including associating a program number and a packet identifier (PID) for a second table, and the second table providing mapping between the program number and the program element for the 3D content, and wherein the second table comprises first information specifying that a type of the program element carried within transport stream (TS) packets is a video stream, second information specifying an elementary PID of the TS packets which carry the program element, and third information indicating that a video format type of the program element is any one of a side by side format and a top and bottom format.
 2. The receiving system of claim 1, wherein the 3D content comprises a left-view image and a right-view image, and wherein the signaling information further includes view identification information, the view identification information indicating whether an image corresponds to the left-view image or the right-view image.
 3. The receiving system of claim 2, wherein the left-view image is assigned to a left image and the right-view image is assigned to a right image.
 4. The receiving system of claim 3, wherein the left-view image has a packet identifier different from that of the right-view image.
 5. The receiving system of claim 3, wherein the decoder independently decodes the left image and the right image.
 6. The receiving system of claim 3, wherein the displaying unit displays a 3D image using the format information of the 3D content and the decoded left and right images.
 7. The receiving system of claim 1, wherein the signaling information further includes image information which is referred to for decoding the 3D content, the image information including view identification information of at least one reference image used for encoding the 3D content.
 8. The receiving system of claim 1, wherein the signaling information further includes information associated with a sampling time difference that can occur between two views configured of the 3D content.
 9. A method of processing data in a receiving system, the method comprising: receiving, by a receiving unit, a broadcast signal comprising a program which carries a program element for a 3-dimensional (3D) content and signaling information of the program, the 3D content comprising images of different views; processing, by a signaling information processor, the signaling information from the broadcast signal; decoding, by a decoder, the program element for the 3D content; and displaying, by a displaying unit, 3D content according to the signaling information, wherein the signaling information includes a first table including associating a program number and a packet identifier (PID) for a second table, and the second table providing mapping between the program number and the program element for the 3D content, and wherein the second table comprises first information specifying that a type of the program element carried within transport stream (TS) packets is a video stream, second information specifying an elementary PID of the TS packets which carry the program element, and third information indicating that a video format type of the program element is any one of a side by side format and a top and bottom format.
 10. The method of claim 9, wherein the 3D content comprises a left-view image and a right-view image, and wherein the signaling information further includes view identification information, the view identification information indicating whether an image corresponds to the left-view image or the right-view image.
 11. The method of claim 10, wherein the left-view image is assigned to a left image and the right-view image is assigned to a right image.
 12. The method of claim 11, wherein the left-view image has a packet identifier different from that of the right-view image.
 13. The method of claim 11, wherein decoding the 3D content independently decodes the left image and the right image.
 14. The method of claim 11, wherein displaying the decoded 3D content displays a 3D image using the format information of the 3D content and the decoded left and right images.
 15. The method of claim 9, wherein the signaling information further includes image information which is referred to for decoding the 3D content, the image information including view identification information of at least one reference image used for encoding the 3D content.
 16. The method of claim 9, wherein the signaling information further includes information associated with a sampling time difference that can occur between two views configured of the 3D content. 